1. Field of the Invention
The present invention relates to a ball-grid-array semiconductor device and a manufacturing method therefor, and more particularly, to a ball-grid-array semiconductor device having a lead frame with terminal portions formed to protrude by etching, and its manufacturing method.
2. Description of the Related Art
A package including a lead frame is available as one of semiconductor device packages that have been manufactured to meet the requirements for semiconductor devices such as higher-integration, miniaturization, decreasing in thickness, and higher pin count. A technique relating to a method for manufacturing lead frames that is applicable to ball-grid-array semiconductor devices is described in Japanese Patent Application Laid-Open No. Sho 60 (1985)-52050. FIG. 1 is a cross-sectional view showing a conventional semiconductor device having a lead frame described in Japanese Patent Application Laid-Open No. Sho 60 (1985)-52050.
According to the prior art described in this publication, in a process where a sheet of metal is etched to form a lead frame, approximately a half of one side of the metal sheet is etched. This allows for forming projected portions 110a for use as external terminals on the side, which protrude in the direction of thickness of the metal sheet. Subsequently, an integrated circuit 114 is attached with a bonding portion 112 to the other side where the projected portions 110a of the lead frame 110 have not been formed. Then, these are sealed with resin 118. At this time, edges of the projected portions 110a and part of the sides of the resin 118 are coplanar. For the conventional semiconductor devices, such method was employed to manufacture the lead frame 110 having terminals for external connection in one process.
However, this presents a problem that it is difficult to clean flux residues remaining between a package and a substrate after the package has been mounted onto the substrate. This happens because the edges of the projected portions 110a, or external terminals, and part of sides of the resin 118 are coplanar.
A method of mounting solder balls onto the projected portions 110a is available to solve this problem, however, this method also presents a problem that material and manufacturing costs are hardly reduced.
An object of the present invention is to provide a ball-grid-array semiconductor device and manufacturing method therefor, which facilitates cleaning flux residues remaining in between the package and the substrate after having been mounted onto the substrate, and which provides drastically reduced material and manufacturing costs.
According to one aspect of the present invention, a ball-grid-array semiconductor device comprises: a semiconductor element; a resin material which seals the semiconductor element; and a lead frame connected to the semiconductor element in the resin material. The lead frame has a terminal portion that protrudes through a surface of the resin material.
According to another aspect of the present invention, a method for manufacturing a ball-grid-array semiconductor device comprises the steps of: forming a lead frame having a terminal portion that protrudes in the direction of thickness thereof; mounting a semiconductor element on the lead frame; connecting an electrode provided on the semiconductor device to the lead frame by means of a bonding wire; and sealing the semiconductor element with a resin material. The terminal portion protrudes through a surface of the resin material.
The present invention allows the terminal portions to protrude through the surface of the resin material. Thus, the terminal portions can used as connecting terminals, as they are, to be mounted directly to the substrate, and cleaning of flux residues after mounting can be readily carried out. Therefore, conventional ball-grid-array semiconductor devices have required solder balls to be mounted on packages to facilitate cleaning flux residues, whereas the present invention requires no such necessity, allowing for providing remarkably reduced material and manufacturing costs.